1 Sleep Disorders Centre, Guy's and St Thomas' NHS Foundation Trust, London SE1 1UL, UK. Electronic address: laura.perezcarbonell@gstt.nhs.uk.
2 Center for Narcolepsy, Stanford University, Palo Alto, CA, USA.
3 Sleep Disorders Centre, Guy's and St Thomas' NHS Foundation Trust, London SE1 1UL, UK; Basic and Clinical Neurosciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
4 Centre National de Référence Narcolepsie Hypersomnies, Unité des Troubles du Sommeil, Département de Neurologie, Hôpital Gui-de-Chauliac, Inserm INM, Université Montpellier, Montpellier, France.